[RTTY] If you care about CW and RTTY - time is of the essence

[Joe Subich, W4TV]

Let me give you some starting points ...

1) Most the "Normal" narrow band amateur digital modes fit in a
    400 Hz bandwidth.  This includes RTTY at 45, 50, 75, 100 baud;
    PSK31/PSK63/PSK125/PSK250, ASCII at 110 baud, HF packet at 300
    baud, 200HZ shift, the original PACTOR (PACTOR 1) and narrow
    versions of Olivia, DominoEX, Contestia, MFSK, etc.

2) There is no justification for any [digital] mode to use more
    than 2.7 KHz.  There are modulation methods (like MS-118-110
    and NATO STANAG) that are capable of data rates to 19,200 bps
    in a 2.7 KHz channel - consistent with amateur practice - that
    are both more efficient and faster than proposed PACTOR 4.
    These modes would become "legal" once the symbol rate limitation
    is removed.

3) As it stands with no limitation on symbol rate and no bandwidth
    limit, the Commission's proposal provides no protection for
    traditional narrow modes against interference from new manually
    operated high speed modes where the operator does not listed
    to the received audio or monitor an audio spectrum/waterfall
    capable of clearly displaying a -135 dBm signal in a 500 Hz
    bandwidth (typical CW minimum discernible signal).

4) limiting occupied bandwidth in those bands below 29.5 MHz
    currently allocated to RTTY/Digital to 400 Hz and allowing
    RTTY/DATA signals up to 2.7 KHz bandwidth wherever VOICE/IMAGE
    is now permitted would align the occupied bandwidth (narrow
    with narrow, wide with wide) just as is the case today (e.g.,
    narrow *IMAGE MODES*, e.g., Hellschreiber, are permitted to
    coexist with narrow RTTY/DATA modes while wide image modes,
    e.g., SSTV is allocated along side the "wider" (2.7 KHz) voice
    modes.

Again, the "smart solution" is to eliminate frequency restrictions on
RTTY/DATA below 29.5 MHz (except 60 meters), establish a 400 Hz
bandwidth limitation for those frequencies where voice/image emissions
are not currently permitted and establish a 2.7 KHz bandwidth limit
(with a specific 6 KHz exemption for double sideband AM) for all
frequencies below 29.5 MHz where voice/image emissions are currently
permitted.  In addition, consideration should be given to require any
operator using *any emission* where the receiver audio is not being
continuously monitored "by ear" to employ visual means (audio spectrum
or waterfall display) to determine if any other signal -135 dBm or
greater currently using the frequency to prevent interference.

73,

    ... Joe, W4TV



On 8/8/2016 12:08 PM, Ron WT7AA wrote:
>
> SSB is 'designed' to occupy a small bandwidth, yet I can routinely
> hear Southern Cross at least 8kHz away from their center freq.  During
> RTTY contests, I hear the old 300 baud packet showing up, but never at
> any other time.  NTS hasn't been a useful service in decades, and some
> new 'improved' and 'better than those old modulations' scheme will not
> change that, that information theory says otherwise (and experience
> proves) is ignored.  The threat of interference is not to be dismissed
> with a unbacked claim of FUD.
>
> But I do say give them a chance to prove themselves, and that only
> requires a Special Temporary Authority not a rule change.  That
> Authority should go on for a few years, so that all of the 'gotta try
> something new this week' ops drop out and we see how few are left and
> if they deserve special priviledges that dislodge the majority.
>
>
>> Date: Mon, 08 Aug 2016 07:19:39 -0400
>> From: Matthew Pitts via RTTY <rtty at contesting.com>
>>
>> A fine example of FUD, since neither the ARRL or FCC are changing
>> 97.221 in any way, nor is it likely that any significant increase in
>> interference will result with "new" technologies already having a
>
>> means to prevent interference as part of their design.
>>
>> Matthew Pitts
>> N8OHU
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